Light emitting diode display device

ABSTRACT

Discussed is a light emitting diode display device including a plurality of pixels displaying an image based on a data signal, the plurality of pixels each including: a first and second light emitting diode devices emitting light, a first and second driving transistors electrically connected to the first and second light emitting diode devices respectively, an insulation layer covering the first and second driving transistors and a planarization layer on the insulation layer and an adhesive member between the insulation layer and the first and the second light emitting diode devices, wherein each of the first and second light emitting diode devices includes: a first portion including a first electrode and a second electrode and a second portion opposite to the first portion, and wherein the adhesive member is interposed between the second portion of each of the first and the second light emitting diode devices and the insulation layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.15/845,771 filed on Dec. 18, 2017, which claims the priority benefit ofKorean Patent Application No. 10-2016-0173807 filed on Dec. 19, 2016,the entire contents of all these applications are hereby expresslyincorporated by reference into the present application.

BACKGROUND OF THE INVENTION Field of the Invention

Embodiments of the present disclosure relate to a light emitting diodedisplay device.

Discussion of the Related Art

Liquid crystal display (LCD) devices are being widely used as a displayscreen of notebook computers, tablet computers, smartphones, portabledisplay devices, and portable information devices in addition to adisplay screen of television (TVs) and monitors.

LCD devices and organic light emitting display devices display an imageby using thin film transistors (TFTs) as switching elements. Since theLCD devices cannot self-emit light, the LCD devices display an image byusing light emitted from a backlight unit which is disposed under aliquid crystal display panel. Since the LCD devices include a backlightunit, a design of the LCD devices is limited, and luminance and aresponse time are reduced. Since the organic light emitting displaydevices include an organic material, the organic light emitting displaydevices are vulnerable to water, causing a reduction in reliability andlifetime.

Recently, research and development on light emitting diode displaydevices including a micro light emitting device are being performed. Thelight emitting diode display devices have high image quality and highreliability, and thus, are attracting much attention as next-generationdisplay devices.

However, in a related art light emitting diode display device, a screendefect occurs due to a defect of a micro light emitting diode devicewhich occurs in a process of transferring a micro light emitting deviceonto a TFT array substrate.

SUMMARY OF THE INVENTION

Accordingly, the present disclosure is directed to provide a lightemitting diode display device that substantially obviates one or moreproblems due to limitations and disadvantages of the related art.

An aspect of the present disclosure is directed to provide a lightemitting diode display device for minimizing a screen defect caused by adefect of a light emitting diode device.

Additional advantages and features of the disclosure will be set forthin part in the description which follows and in part will becomeapparent to those having ordinary skill in the art upon examination ofthe following or may be learned from practice of the disclosure. Theobjectives and other advantages of the disclosure may be realized andattained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

To achieve these and other advantages and in accordance with the purposeof the disclosure, as embodied and broadly described herein, there isprovided a light emitting diode display device including a plurality ofsubpixels which each include first to Nth (where N is a natural numberequal to or greater than two) light emitting diode devices emittinglight with the data current and a pixel circuit including first to Nthdriving transistors respectively supplying the data currentcorresponding to a data signal to the first to Nth light emitting diodedevices.

It is to be understood that both the foregoing general description andthe following detailed description of the present disclosure are byexample and explanatory and are intended to provide a furtherexplanation of the disclosure as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure and are incorporated in and constitute apart of this application, illustrate embodiments of the disclosure andtogether with the description serve to explain the principle of thedisclosure. In the drawings:

FIG. 1 is a diagram for describing a light emitting diode display deviceaccording to an embodiment of the present disclosure;

FIG. 2 is a diagram for describing a unit pixel illustrated in FIG. 1;

FIG. 3 is a diagram illustrating one subpixel illustrated in FIG. 2;

FIG. 4 is a cross-sectional view for describing a subpixel structureillustrated in FIG. 3;

FIG. 5 is a cross-sectional view for describing a structure of a lightemitting diode device illustrated in FIG. 4;

FIG. 6 is a diagram for describing a modification embodiment of aconcave portion illustrated in FIG. 2; and

FIG. 7 is a diagram for describing a subpixel according to an embodimentof the present disclosure illustrated in FIG. 2.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the example embodiments of thepresent disclosure, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numberswill be used throughout the drawings to refer to the same or like parts.

Advantages and features of the present disclosure, and implementationmethods thereof will be clarified through following embodimentsdescribed with reference to the accompanying drawings. The presentdisclosure may, however, be embodied in different forms and should notbe construed as limited to the embodiments set forth herein. Rather,these embodiments are provided so that this disclosure will be thoroughand complete, and will fully convey the scope of the present disclosureto those skilled in the art. Furthermore, the present disclosure is onlydefined by the scopes of the claims.

A shape, a size, a ratio, an angle, and a number disclosed in thedrawings for describing embodiments of the present disclosure are merelyan example, and thus, the present disclosure is not limited to theillustrated details. Like reference numerals refer to like elementsthroughout. In the following description, when the detailed descriptionof the relevant known technology is determined to unnecessarily obscurethe important point of the present disclosure, the detailed descriptionwill be omitted.

In an instance where ‘comprise’, ‘have’, and ‘include’ described in thepresent specification are used, another part or an element may be addedor included unless ‘only˜’ is used. The terms of a singular form mayinclude plural forms unless referred to the contrary.

In construing an element, the element is construed as including an errorrange although there is no explicit description.

In describing a position relationship, for example, when a positionrelation between two parts is described as ‘on˜’, ‘over˜’, ‘under˜’, and‘next˜’, one or more other parts may be disposed between the two partsunless ‘just’ or ‘direct’ is used.

In describing a time relationship, for example, when the temporal orderis described as ‘after˜’, ‘subsequent˜’, ‘next˜’, and ‘before˜’, aninstance which is not continuous may be included unless ‘just’ or‘direct’ is used.

It will be understood that, although the terms “first”, “second”, etc.may be used herein to describe various elements, these elements shouldnot be limited by these terms. These terms are only used to distinguishone element from another. For example, a first element could be termed asecond element, and, similarly, a second element could be termed a firstelement, without departing from the scope of the present disclosure.

A first horizontal axis direction, a second horizontal axis direction,and a vertical axis direction should not be construed as only ageometric relationship where a relationship therebetween is vertical,and may denote having a broader directionality within a scope whereelements of the present disclosure operate functionally.

The term “at least one” should be understood as including any and allcombinations of one or more of the associated listed items. For example,the meaning of “at least one of a first item, a second item, and a thirditem” denotes the combination of all items proposed from two or more ofthe first item, the second item, and the third item as well as the firstitem, the second item, or the third item.

Features of various embodiments of the present disclosure may bepartially or overall coupled to or combined with each other, and may bevariously inter-operated with each other and driven technically as thoseskilled in the art can sufficiently understand. The embodiments of thepresent disclosure may be carried out independently from each other, ormay be carried out together in co-dependent relationship.

Hereinafter, example embodiments of a light emitting diode displaydevice according to the present disclosure will be described in detailwith reference to the accompanying drawings. In the specification, inadding reference numerals for elements in each drawing, it should benoted that like reference numerals already used to denote like elementsin other drawings are used for elements wherever possible.

FIG. 1 is a diagram for describing a light emitting diode display deviceaccording to an embodiment of the present disclosure, FIG. 2 is adiagram for describing a unit pixel illustrated in FIG. 1, and FIG. 3 isa diagram illustrating one subpixel illustrated in FIG. 2.

Referring to FIGS. 1 to 3, the light emitting diode display deviceaccording to an embodiment of the present disclosure may include a firstsubstrate 100 including a plurality of subpixels SP1 to SP3 and a secondsubstrate 500 which is opposite-bonded to the first substrate 100 tocover the plurality of subpixels SP1 to SP3.

The first substrate 100 may be a thin film transistor (TFT) arraysubstrate and may be formed of glass, a plastic material, and/or thelike. The first substrate 100 according to an embodiment may include adisplay area (or an active area) AA and a non-display area (or aninactive area) IA.

The display area AA may be provided in a portion other than an edge ofthe first substrate 100. The display area AA may be defined as an areawhere a subpixel array including the plurality of subpixels SP1 to SP3displaying an image is provided.

The non-display area IA may be provided in a portion other than thedisplay area AA provided on the first substrate 100 and may be definedas the edge of the first substrate 100 surrounding the display area AA.The non-display area IA may be a peripheral portion outside the displayarea AA and cannot display an image unlike the display area AA, andmoreover, the non-display area IA may be defined as an area where linesand circuits for driving the subpixel (SP) array are disposed. Forexample, the non-display area IA may include a first non-display areadefined near an upper side of the display area AA, a second non-displayarea defined near a lower side of the display area AA, a thirdnon-display area defined near a left side of the display area AA, and afourth non-display area defined near a right side of the display areaAA.

The first substrate 100 according to an embodiment may include aplurality of gate lines GL, a plurality of data lines DL, a plurality ofdriving power lines PL, a plurality of common power lines CL, and aplurality of subpixels SP1 to SP3.

The plurality of gate lines GL may be provided on the first substrate100, may long extend along a first horizontal axis direction X of thefirst substrate 100, may be arranged along a second horizontal axisdirection Y, and may be spaced apart from each other by a certaininterval. In this instance, the first horizontal axis direction X may bedefined as a direction parallel to a long side length direction of thefirst substrate 100, and the second horizontal axis direction Y may bedefined as a direction parallel to a short side length direction of thefirst substrate 100. Alternatively, each of the first horizontal axisdirection X and the second horizontal axis direction Y may be defined asa direction opposite thereto.

The plurality of data lines DL may be provided on the first substrate100 to intersect the plurality of gate lines GL, may long extend alongthe second horizontal axis direction Y of the first substrate 100, maybe arranged along the first horizontal axis direction X, and may bespaced apart from each other by a certain interval.

The plurality of driving power lines PL may be provided on the firstsubstrate 100 in parallel with the plurality of data lines DL and may beformed along with the plurality of data lines DL. Each of the pluralityof driving power lines PL may supply a pixel driving power, suppliedfrom the outside, to the subpixels SP1 to SP3.

The plurality of common power lines CL may be arranged on the firstsubstrate 100 in parallel with the plurality of data lines DL and may beformed along with the plurality of data lines DL. Each of the pluralityof common power lines CL may supply a common power, supplied from theoutside, to the subpixels SP1 to SP3.

Optionally, each of the plurality of common power lines CL mayindividually receive the common power supplied from the outside and mayindividually supply the common power to each of the subpixels SP1 toSP3. In this instance, a voltage level of the common power supplied toeach of the subpixels SP1 to SP3 may be controlled based on anelectrical characteristic change of a below-described light emittingdiode device and/or an electrical characteristic change of abelow-described driving TFT.

The plurality of subpixels SP1 to SP3 may be respectively provided in aplurality of pixel areas defined by intersections of the gate lines GLand the data lines DL. Each of the plurality of subpixels SP1 to SP3 maybe defined as an area corresponding to a minimum unit where light isactually emitted. At least three adjacent subpixels SP1 to SP3 mayconfigure one unit pixel UP for displaying colors. For example, the oneunit pixel UP may include a red subpixel SP1, a green subpixel SP2, anda blue subpixel SP3 which are adjacent to each other, and may furtherinclude a white subpixel for enhancing luminance.

At least three subpixels SP1 to SP3 configuring a unit pixel UPaccording to an embodiment may share one driving power line PL, and inthis instance, each of the plurality of power driving lines PL may beprovided in one corresponding unit pixel of a plurality of unit pixelsUP, thereby reducing the number of the driving power lines PL providedon the first substrate 100. Likewise, at least three subpixels SP1 toSP3 configuring a unit pixel UP according to an embodiment may share onecommon power line CL, and in this instance, each of the plurality ofcommon power lines CL may be provided in one corresponding unit pixel ofthe plurality of unit pixels UP, thereby reducing the number of thecommon power line CL provided on the first substrate 100.

The plurality of subpixels SP1 to SP3 may each include first and secondlight emitting diode devices 300 a and 300 b which emit light with adata current, and a pixel circuit PC including first and second drivingtransistors Tdr1 and Tdr2 which respectively supply the data currentcorresponding to a data signal to the first and second light emittingdiode devices 300 a and 300 b.

The first light emitting diode device 300 a may be disposed on one sideof a pixel area and may be connected to the pixel circuit PC, and thus,may emit light having brightness proportional to the data currentsupplied from the pixel circuit PC, namely, the first driving transistorTdr1. The first light emitting diode device 300 a according to anembodiment may be a light emitting diode chip which emits one of redlight, green light, blue light, and white light. For example, the firstlight emitting diode device 300 a may be a micro light emitting diodechip. In this instance, the micro light emitting diode chip may have ascale of 1 μm to 100 μm, but is not limited thereto.

The first light emitting diode device 300 a may be disposed on a firstemissive area of the pixel area and may be connected to the pixelcircuit PC and a corresponding common power line CL. That is, the firstlight emitting diode device 300 a according to an embodiment may includean anode terminal (or a first electrode) electrically connected to thepixel circuit PC and a cathode terminal (or a second electrode)electrically connected to the common power line CL. The first lightemitting diode device 300 a may emit light having brightnessproportional to the data current supplied from the pixel circuit PC,namely, the first driving transistor Tdr1. The first light emittingdiode device 300 a according to an embodiment may be a light emittingdiode chip which emits one of red light, green light, blue light, andwhite light. For example, the first light emitting diode device 300 amay be a micro light emitting diode chip including a first electrode anda second electrode. Here, the micro light emitting diode chip may have ascale of 1 μm to 100 μm, but is not limited thereto.

The second light emitting diode device 300 b may be disposed on a secondemissive area which are adjacent to the first emissive area of the pixelarea and may be connected to the pixel circuit PC and the correspondingcommon power line CL. That is, the second light emitting diode device300 b according to an embodiment may include an anode terminal (or afirst electrode) electrically connected to the pixel circuit PC and acathode terminal (or a second electrode) electrically connected to thecommon power line CL. The second light emitting diode device 300 b mayemit light having brightness proportional to the data current suppliedfrom the pixel circuit PC, namely, the second driving transistor Tdr2.The second light emitting diode device 300 b according to an embodimentmay be a light emitting diode chip which emits the same light as lightemitted from the first light emitting diode device 300 a, and forexample, may be a micro light emitting diode chip including an anodeterminal and a cathode terminal.

One of the first and second light emitting diode devices 300 a and 300 bmay be used as a redundancy light emitting diode device for preventing ascreen defect from occurring due to an operation error caused by anelectrical impact or misalignment which occurs in a process of mountingthe first substrate 100.

The pixel circuit PC may be provided in a circuit area of the pixelarea, may be electrically connected to a data line DL, a gate line GL, adriving power line PL, and a common power line CL which are adjacentthereto, and may supply the data current to the anode terminals of thefirst and second light emitting diode devices 300 a and 300 b in common.The pixel circuit PC may supply the data current based on a data signal,supplied through the data line DL, to the anode terminals of the firstand second light emitting diode devices 300 a and 300 b in common inresponse to a gate signal supplied through the gate line GL, therebyallowing each of the first and second light emitting diode devices 300 aand 300 b to emit light with the data current.

The pixel circuit PC according to an embodiment may include a switchingtransistor Tsw, a first current output part COP1, and a second currentoutput part COP2.

The switching transistor Tsw may include a gate electrode connected tothe gate line GL, a drain electrode connected to the data line DL, and asource electrode connected to a common node Nc. In this instance, thesource electrode and the drain electrode of the switching transistor Tswmay switch therebetween depending on a direction of a current. Theswitching transistor Tsw may be turned on according to the gate signalsupplied through the gate line GL and may supply the data signal,supplied through the data line DL, to the common node Nc, namely, eachof the first current output part COP1 and the second current output partCOP2 in common.

The common node Nc may be shared by the first current output part COP1and the second current output part COP2.

The first current output part COP1 may supply a data current,corresponding to the data signal supplied from the switching transistorTsw to the common node Nc, to the first light emitting diode device 300a. The first current output part COP1 according to an embodiment mayinclude a first driving transistor Tdr1 and a first capacitor C1.

The first driving transistor Tdr1 may include a gate electrode connectedto the common electrode Nc, a drain electrode connected to the drivingpower line PL, and a source electrode connected to the anode terminal ofthe first light emitting diode device 300 a. The first drivingtransistor Tdr1 may be turned on by a voltage of the common node Nc tocontrol the amount of current flowing from the driving power line PL tothe first light emitting diode device 300 a. In other words, the firstdriving transistor Tdr1 may control a data current flowing from thedriving power line PL to the first light emitting diode device 300 a,based on the data signal supplied from the switching transistor Tsw tothe common node Nc, thereby allowing the first light emitting diodedevice 300 a to emit light having brightness proportional to the datasignal.

The first capacitor C1 may be connected between the gate electrode andthe source electrode (i.e., a gate-source electrode) of the firstdriving transistor Tdr1. That is, the first capacitor C1 may be providedto have a certain capacitance in an overlapping area between the sourceelectrode and the common node Nc connected to the gate electrode of thefirst driving transistor Tdr1. The first capacitor C1 may store avoltage corresponding to the data signal supplied to the gate electrodeof the first driving transistor Tdr1 and may turn on the first drivingtransistor Tdr1 with the stored voltage.

The second current output part COP2 may supply a data current,corresponding to the data signal supplied from the switching transistorTsw to the common node Nc, to the second light emitting diode device 300b. The second current output part COP2 according to an embodiment mayinclude a second driving transistor Tdr2 and a second capacitor C2.

The second driving transistor Tdr2 may include a gate electrodeconnected to the common electrode Nc, a drain electrode connected to thedriving power line PL, and a source electrode connected to the anodeterminal of the second light emitting diode device 300 b. The seconddriving transistor Tdr2 may be turned on by the voltage of the commonnode Nc to control the amount of current flowing from the driving powerline PL to the second light emitting diode device 300 b. In other words,the second driving transistor Tdr2 may control a data current flowingfrom the driving power line PL to the second light emitting diode device300 b, based on the data signal supplied from the switching transistorTsw to the common node Nc, thereby allowing the second light emittingdiode device 300 b to emit light having brightness proportional to thedata signal.

The second driving transistor Tdr2 may be formed along with the firstdriving transistor Tdr1 and may have the same size as that of the firstdriving transistor Tdr1.

The second capacitor C2 may be connected between the gate electrode andthe source electrode (i.e., a gate-source electrode) of the seconddriving transistor Tdr2. That is, the second capacitor C2 may beprovided to have a certain capacitance in an overlapping area betweenthe source electrode and the common node Nc connected to the gateelectrode of the second driving transistor Tdr2. The second capacitor C2may store a voltage corresponding to the data signal supplied to thegate electrode of the second driving transistor Tdr2 and may turn on thesecond driving transistor Tdr2 with the stored voltage.

The switching transistor Tsw and the first and second drivingtransistors Tdr1 and Tdr2 according to an embodiment may each be anamorphous silicon thin film transistor (TFT), a polycrystalline siliconTFT, an oxide TFT, or an organic material TFT, and each of thetransistors Tsw, Tdr1, and Tdr1 may have a top gate structure, a bottomgate structure, or a double gate structure having the top gate structureand the bottom gate structure.

In the pixel circuit PC, one of the first and second current outputparts COP1 and COP2 may be a redundancy pixel circuit which ispreviously provided in each of subpixels SP1 to SP3 for solving anoperation defect of each of the first and second light emitting diodedevices 300 a and 300 b provided in each of the subpixels SP1 to SP3.

In addition, each of the plurality of subpixels SP1 to SP3 may furtherinclude a first concave portion 130 a accommodating the first lightemitting diode device 300 a and a second concave portion 130 baccommodating the second light emitting diode device 300 b.

The first concave portion 130 a may be provided in the first emissivearea of the pixel area defined in each of the subpixels SP1 to SP3 andmay accommodate the first light emitting diode device 300 a. The firstconcave portion 130 a according to an embodiment may include a firstaccommodation space provided concavely from a planarization layer (or apassivation layer) which is provided to cover the pixel circuit PC.Since the first concave portion 130 a accommodates the first lightemitting diode device 300 a, a misalignment of the first light emittingdiode device 300 a is minimized in a transfer process performed on thefirst light emitting diode device 300 a, and thus, alignment precisionis enhanced. Furthermore, an increase in thickness of a display devicecaused by a thickness (or a height) of the first light emitting diodedevice 300 a is minimized.

The second concave portion 130 b may be provided in the second emissivearea of the pixel area defined in each of the subpixels SP1 to SP3 andmay accommodate the second light emitting diode device 300 b. The secondconcave portion 130 b according to an embodiment may include a secondaccommodation space provided concavely from the planarization layer andmay be provided in the same shape as that of the first concave portion130 a. Since the second concave portion 130 b accommodates the secondlight emitting diode device 300 b, a misalignment of the second lightemitting diode device 300 b is minimized in a transfer process performedon the second light emitting diode device 300 b, and thus, alignmentprecision is enhanced. Furthermore, an increase in thickness of thedisplay device caused by a thickness (or a height) of the second lightemitting diode device 300 b is minimized.

Optionally, the first concave portion 130 a and the second concaveportion 130 b may communicate with each other without a boundarytherebetween. That is, the accommodation space of the first concaveportion 130 a and the accommodation space of the second concave portion130 b may communicate with each other to configure one accommodationspace, and in this instance, the subpixels SP1 to SP3 may each includeone concave portion including one accommodation space where the firstlight emitting diode device 300 a and the second light emitting diodedevice 300 b are provided in parallel. In this instance, in a process ofdisposing the first light emitting diode device 300 a and the secondlight emitting diode device 300 b in the accommodation space of theconcave portion, an alignment process for each of the first lightemitting diode device 300 a and the second light emitting diode device300 b is easily performed.

The second substrate 500 may be disposed to cover the first substrate100 and may be defined as a color filter array substrate, an oppositesubstrate, or an encapsulation substrate. The second substrate 500 maybe opposite-bonded to the first substrate 100 by a sealant surroundingthe display area AA of the first substrate 100.

In addition, the light emitting diode display device according to anembodiment of the present disclosure may further include a gate drivingcircuit 700 and a panel driver 900.

The gate driving circuit 700 may generate the gate signal according to agate control signal input from the panel driver 900 and may supply thegate signal to the gate lines GL. The gate driving circuit 700 accordingto an embodiment may be built into the third non-display area of thefirst substrate 100 through a process which is the same as a process offorming TFTs provided in each subpixel SP. For example, the gate drivingcircuit 700 may be provided in a left and/or right non-display area withrespect to the display area AA, but is not limited thereto. In otherembodiments, the gate driving circuit 700 may be provided in anarbitrary non-display area which enables the gate signal to be suppliedto the gate lines GL.

Optionally, the gate driving circuit 700 may be manufactured as adriving integrated circuit (IC) type. In this instance, the gate drivingcircuit 700 according to an embodiment may be mounted in the thirdand/or fourth non-display area of the first substrate 100 so as to beconnected to a plurality of gate lines in a one-to-one correspondencerelationship. According to another embodiment, the gate driving circuit700 may be mounted on a gate flexible circuit film, and in thisinstance, the gate flexible circuit film may be attached on a gate padpart provided in the third and/or fourth non-display area of the firstsubstrate 100, whereby the gate driving circuit 700 may be connected tothe plurality of gate lines through the gate flexible circuit film andthe gate pad part in a one-to-one correspondence relationship.

The panel driver 900 may be connected to a pad part provided in thefirst non-display area of the first substrate 100 and may display animage, corresponding to image data supplied from a display drivingsystem, on the display area AA. The panel driver 900 according to anembodiment may include a plurality of data flexible circuit films 910, aplurality of data driving ICs 930, a printed circuit board (PCB) 950, atiming controller 970, and a power circuit 990.

Each of the plurality of data flexible circuit films 910 may be attachedon the pad part of the first substrate 100 through a film attachmentprocess.

Each of the plurality of data driving ICs 930 may be individuallymounted on a corresponding data flexible circuit film of the pluralityof data flexible circuit films 910. The data driving ICs 930 may receivesubpixel data and a data control signal supplied from the timingcontroller 970, convert the subpixel data into analog data voltages bysubpixels according to the data control signal, and respectively supplythe analog data voltages to the data lines DL.

The PCB 950 may be connected to the plurality of data flexible circuitfilms 910. The PCB 950 may support the timing controller 970 and thepower circuit 990 and may transfer signals and power between theelements of the panel driver 900.

The timing controller 970 may be mounted on the PCB 950 and may receiveimage data and a timing synchronization signal supplied from the displaydriving system through a user connector provided on the PCB 950. Thetiming controller 970 may align the image data according to a subpixelarrangement structure of the display area AA based on the timingsynchronization signal to generate subpixel data and may supply thegenerated subpixel data to the data driving ICs 930. Also, the timingcontroller 970 may generate the data control signal and the gate controlsignal, based on the timing synchronization signal and may control adriving timing of each of the data driving ICs 930 and the gate drivercircuit 700.

The power circuit 990 may be mounted on the PCB 950 and may generatevarious voltages necessary for displaying an image on the display areaAA by using an input power received from the outside to supply each ofthe voltages to a corresponding element.

The panel driver 900 may further include a control board connected tothe PCB 950. In this instance, the timing controller 970 and the powercircuit 990 may be mounted on the control board without being mounted onthe PCB 950. Accordingly, the PCB 950 may perform only a function oftransferring signals and power between the plurality of data flexiblecircuit films 910 and the control board.

The light emitting diode display device according to the presentembodiment may include a redundancy light emitting diode device and aredundancy pixel circuit provided in each of the subpixels SP1 to SP3,thereby minimizing or preventing a screen defect caused by a defect ofthe light emitting diode device transferred onto each of the subpixelsSP1 to SP3. Also, in the light emitting diode display device accordingto the present embodiment, since the first and second light emittingdiode devices 300 a and 300 b are accommodated into at least one concaveportion provided in each of the subpixels SP1 to SP3, a misalignment ofthe light emitting diode devices is minimized in the transfer processfor the light emitting diode devices, and the light emitting diodedisplay device has a thin thickness.

In an embodiment of the present disclosure, as shown in FIG. 3, forexample, the subpixel SP1 including the first light emitting diode 300 aand the second light emitting diode 300 b may have first electrodes ofthe first and second light emitting diodes 300 a, 300 b being commonlyconnected, and second electrodes of the first and second light emittingdiodes 300 a, 300 b being commonly connected. Also, a distance betweenthe second electrodes of the first and second light emitting diodes 300a, 300 b may be smaller than a distance between the first electrodes ofthe first and second light emitting diodes 300 a, 300 b.

FIG. 4 is a cross-sectional view for describing a subpixel structureillustrated in FIG. 3, and FIG. 5 is a cross-sectional view fordescribing a structure of a light emitting diode device illustrated inFIG. 4.

Referring to FIGS. 4 and 5 along with FIG. 3, a subpixel SP of a lightemitting diode display device according to the present embodiment mayinclude a pixel circuit PC, a first planarization layer 110, first andsecond concave portions 130 a and 130 b, first and second light emittingdiode devices 300 a and 300 b, a second planarization layer 160, a firstpixel electrode AE1, a second pixel electrode AE2, and a commonelectrode CE.

The pixel circuit PC may include a first current output part COP1,including a switching transistor Tsw, a first driving transistor Tdr1,and a first capacitor C1, and a second current output part COP2including a second driving transistor Tdr2 and a second capacitor C2.The pixel circuit PC is as described above, and thus, its detaileddescription is omitted. Hereinafter, only a structure of each of thefirst and second driving transistors Tdr1 and Tdr2 will be described.

The first driving transistor Tdr1 may be provided in a first circuitarea A1 defined in the subpixel SP and may include a gate electrode GE,a semiconductor layer SCL, an ohmic contact layer OCL, a sourceelectrode SE, and a drain electrode DE.

The gate electrode GE may be formed on the first substrate 100 alongwith the gate lines GL. The gate electrode GE may be covered by a gateinsulation layer 103.

The gate insulation layer 103 may be formed of a single layer or amultilayer including an inorganic material and may be formed of siliconoxide (SiOx) silicon nitride (SiNx), and/or the like.

The semiconductor layer SCL may be provided in a predetermined pattern(or island) type on the gate insulation layer 103 to overlap the gateelectrode GE. The semiconductor layer SCL may be formed of asemiconductor material including one of amorphous silicon,polycrystalline silicon, oxide, and an organic material, but is notlimited thereto.

The ohmic contact layer OCL may be provided in a predetermined pattern(or island) type on the semiconductor layer SCL. In this instance, theohmic contact layer OCL is for an ohmic contact between thesemiconductor layer SCL and the source and drain electrodes SE and DEand may be omitted.

The source electrode SE may be formed on one side of the ohmic contactlayer OCL to overlap one side of the semiconductor layer SCL. The sourceelectrode SE may be formed along with the data lines DL and the drivingpower lines PL.

The drain electrode DE may be formed on the other side of the ohmiccontact layer OCL to overlap the other side of the semiconductor layerSCL and may be spaced apart from the source electrode SE. The drainelectrode DE may be formed along with the source electrode SE and maybranch or protrude from an adjacent driving power line PL.

The second driving transistor Tdr2 may be provided in a second circuitarea A2 defined in the subpixel SP and may include a gate electrode GE,a semiconductor layer SCL, an ohmic contact layer OCL, a sourceelectrode SE, and a drain electrode DE. The second driving transistorTdr2 may be formed in the same structure through the same process as thefirst driving transistor Tdr1, and thus, its detailed description isomitted or is briefly described below.

In addition, the switching transistor Tsw configuring the pixel circuitPC may be formed in the same structure through the same process alongwith the first and second driving transistors Tdr1 and Tdr2. In thisinstance, the gate electrode of the switching transistor Tsw may branchor protrude from the gate line GL, the drain electrode of the switchingtransistor Tsw may branch or protrude from the data line DL, and thesource electrode of the switching transistor Tsw may be connected to thecommon node Nc, connected to the gate electrode GE of each of the firstand second driving transistors Tdr1 and Tdr2, through a via holeprovided in the gate insulation layer 103.

The pixel circuit PC may be covered by an interlayer insulation layer105. The interlayer insulation layer 105 may be provided all over thefirst substrate 100 to cover the pixel circuit PC. The interlayerinsulation layer 105 according to an embodiment may be formed of aninorganic material, such as SiOx or SiNx, or an organic material such asbenzocyclobutene or photo acryl. The interlayer insulation layer 105 maybe not provided.

The first planarization layer (or the passivation layer) 110 may beprovided all over the first substrate 100 to cover the subpixel SP(i.e., the pixel circuit PC), or may be provided all over the firstsubstrate 100 to cover the interlayer insulation layer 105. The firstplanarization layer 110 may protect the pixel circuit PC and may providea planar surface on the interlayer insulation layer 105.

The first planarization layer 110 according to an embodiment may beformed of an organic material such as benzocyclobutene or photo acryl,and particularly, may be formed of photo acryl for convenience of aprocess.

The first concave portion 130 a may be provided in a first emissive areadefined in the subpixel SP and may accommodate the first light emittingdiode device 300 a. The first concave portion 130 a according to anembodiment may be concavely provided to have a certain depth D1 from thefirst planarization layer 110. In this instance, the first concaveportion 130 a may include a first accommodation space which is providedconcavely from a top 110 a of the first planarization layer 110 to havethe depth D1 corresponding to a thickness (or a total height) of thefirst light emitting diode device 300 a. In this instance, a floorsurface of the first concave portion 130 a may be formed by removing aportion of the first planarization layer 110, a whole portion of thefirst planarization layer 110, the whole portion of the firstplanarization layer 110 and a portion of the interlayer insulation layer105, or a whole portion of each of the first planarization layer 110,the interlayer insulation layer 105, and the gate insulation layer 103,in order to have the depth D1 which is set based on the thickness of thefirst light emitting diode device 300 a. For example, the first concaveportion 130 a may be provided to have a depth of 2 μm to 6 μm from thetop 110 a of the first planarization layer 110. The first concaveportion 130 a may have a groove or cup shape having a size which iswider than a rear surface (or a bottom) of the first light emittingdiode device 300 a.

The second concave portion 130 b may be provided in a second emissivearea defined in the subpixel SP and may accommodate the second lightemitting diode device 300 b. The second concave portion 130 b accordingto an embodiment may include a second accommodation space which isconcavely provided to have the certain depth D1 from the firstplanarization layer 110. The second concave portion 130 b may be formedin the same shape simultaneously with the first concave portion 130 a,and thus, its detailed description is omitted.

In addition, the first concave portion 130 a and the second concaveportion 130 b may communicate with each other without a boundary 130 ctherebetween. That is, the accommodation space of the first concaveportion 130 a and the accommodation space of the second concave portion130 b may communicate with each other to configure one accommodationspace, and in this instance, the subpixels SP1 to SP3 may each includeone concave portion. In this instance, the first light emitting diodedevice 300 a may be accommodated into one region of the concave portion,and the second light emitting diode device 300 b may be accommodatedinto the other region of the concave portion in parallel with the firstlight emitting diode device 300 a. Therefore, according to the presentembodiment, in a process of disposing the first light emitting diodedevice 300 a and the second light emitting diode device 300 b in theaccommodation space of the concave portion, an alignment process foreach of the first light emitting diode device 300 a and the second lightemitting diode device 300 b is easily performed. Also, according to thepresent embodiment, a light-oriented angle of each of the first lightemitting diode device 300 a and the second light emitting diode device300 b disposed in the concave portion increases, and thus, a darkportion between the first light emitting diode device 300 a and thesecond light emitting diode device 300 b is minimized, therebyminimizing hot spots caused by the dark portion between the first lightemitting diode device 300 a and the second light emitting diode device300 b.

The first light emitting diode device 300 a and the second lightemitting diode device 300 b may each include a light emitting layer EL,a first electrode (or an anode terminal) E1, and a second electrode (ora cathode terminal) E2.

The light emitting layer EL may emit light according to a recombinationof an electron and a hole based on a current flowing between the firstelectrode E1 and the second electrode E2. The light emitting layer ELaccording to an embodiment may include a first semiconductor layer 310,an active layer 330, and a second semiconductor layer 350.

The first semiconductor layer 310 may supply an electron to the activelayer 330. The first semiconductor layer 310 according to an embodimentmay be formed of an n-GaN-based semiconductor material, and examples ofthe n-GaN-based semiconductor material may include GaN, AlGaN, InGaN,AlInGaN, etc. In this instance, silicon (Si), germanium (Ge), selenium(Se), tellurium (Te), or carbon (C) may be used as impurities used fordoping of the first semiconductor layer 310.

The active layer 330 may be provided on one side of the firstsemiconductor layer 310. The active layer 330 may have a multi quantumwell (MQW) structure which includes a well layer and a barrier layerwhich is higher in band gap than the well layer. The active layer 330according to an embodiment may have an MQW structure of InGaN/GaN or thelike.

The second semiconductor layer 350 may be provided on the active layer330 and may supply a hole to the active layer 330. The secondsemiconductor layer 350 according to an embodiment may be formed of ap-GaN-based semiconductor material, and examples of the p-GaN-basedsemiconductor material may include GaN, AlGaN, InGaN, AlInGaN, etc. Inthis instance, magnesium (Mg), zinc (Zn), or beryllium (Be) may be usedas impurities used for doping of the second semiconductor layer 350.

The first electrode E1 may be provided on the second semiconductor layer350. The first electrode E1 may be connected to the source electrode SEof each of the first and second driving transistors Tdr1 and Tdr2.

The second electrode E2 may be provided on the other side of the firstsemiconductor layer 310 and may be electrically and/or physicallydisconnected or separated from the active layer 330 and the secondsemiconductor layer 350. The second electrode E2 may be connected to thecommon power line CL.

Each of the first and second electrodes E1 and E2 according to anembodiment may be formed of a material including one or more materialsof a metal material, such as gold (Au), tungsten (W), platinum (Pt),silicon (Si), iridium (Ir), silver (Ag), copper (Cu), nickel (Ni),titanium (Ti), or chromium (Cr), and an alloy thereof. In otherembodiments, each of the first and second electrodes E1 and E2 may beformed of a transparent conductive material, and examples of thetransparent conductive material may include indium tin oxide (ITO),indium zinc oxide (IZO), etc. However, the present embodiment is notlimited thereto.

In addition, the first semiconductor layer 310, the active layer 330,and the second semiconductor layer 350 may be provided in a structure ofbeing sequentially stacked on a semiconductor substrate. In thisinstance, the semiconductor substrate may include a semiconductormaterial included in a sapphire substrate or a silicon substrate. Thesemiconductor substrate may be used as a growth semiconductor substratefor growing each of the first semiconductor layer 310, the active layer330, and the second semiconductor layer 350, and then, may be separatedfrom the first semiconductor layer 310 through a substrate separationprocess. In this instance, the substrate separation process may be alaser lift-off process or a chemical lift-off process. Therefore, sincethe growth semiconductor substrate is removed from the first and secondlight emitting diode devices 300 a and 300 b, each of the first andsecond light emitting diode devices 300 a and 300 b has a thinthickness, and thus, may be accommodated into the concave portionprovided in the subpixel SP.

Each of the first and second light emitting diode devices 300 a and 300b may emit light according to a recombination of an electron and a holebased on a current flowing between the first electrode E1 and the secondelectrode E2. In this instance, the light emitted from each of the firstand second light emitting diode devices 300 a and 300 b may pass throughthe first and second electrodes E1 and E2 and may be output to theoutside. In other words, the light emitted from each of the first andsecond light emitting diode devices 300 a and 300 b may pass through thefirst and second electrodes E1 and E2 and may be output in a seconddirection opposite to a first direction toward the floor surface of eachof the concave portions 130 a and 130 b, thereby displaying an image.

Each of the first and second light emitting diode devices 300 a and 300b may include a first portion FP, including the first and secondelectrodes E1 and E2 connected to the pixel circuit PC, and a secondportion RP opposite to the first portion FP. In this instance, the firstportion FP may be disposed relatively farther away from the floorsurface of the concave portion than the second portion RP. That is, thefirst and second electrodes E1 and E2 provided in the first portion FPmay be disposed to face the second substrate 500 without being disposedto face the floor surface of the concave portion. In this instance, thefirst portion FP may have a size which is smaller than the secondportion RP, and in this instance, each of the first and second lightemitting diode devices 300 a and 300 b may have a cross-sectionalsurface having a trapezoid shape which includes an upper surfacecorresponding to the first portion FP and a lower surface correspondingto the second portion RP.

The second planarization layer 160 may be provided on the firstplanarization layer 110 to cover the first and second light emittingdiode devices 300 a and 300 b. That is, the second planarization layer160 may be provided on the first planarization layer 110 to have athickness for covering a top of the first planarization layer 110, theother first accommodation space of the first concave portion 130 a withthe first light emitting diode device 300 a accommodated thereinto, theother second accommodation space of the second concave portion 130 bwith the second light emitting diode device 300 b accommodatedthereinto, a front surface of the first light emitting diode device 300a, and a front surface of the second light emitting diode device 300 b.

The second planarization layer 160 may provide a planar surface on thefirst planarization layer 110. Also, the second planarization layer 160may bury the other first accommodation space of the first concaveportion 130 a with the first light emitting diode device 300 aaccommodated thereinto and the other second accommodation space of thesecond concave portion 130 b with the second light emitting diode device300 b accommodated thereinto to fix a position of each of the firstlight emitting diode device 300 a and the second light emitting diodedevice 300 b.

The first pixel electrode AE1 may electrically connect the firstelectrode E1 of the first light emitting diode device 300 a to thesource electrode SE of the first driving transistor Tdr1 and may bedefined as a first anode electrode. The first pixel electrode AE1according to an embodiment may be provided on the second planarizationlayer 160 overlapping the first driving transistor Tdr1 and the firstelectrode E1 of the first light emitting diode device 300 a. The firstpixel electrode AE1 may be electrically connected to the sourceelectrode SE of the first driving transistor Tdr1 through a firstcircuit contact hole CCH1 which is provided to pass through theinterlayer insulation layer 105, the first planarization layer 110, andthe second planarization layer 160, and may be electrically connected tothe first electrode E1 of the first light emitting diode device 300 athrough a first electrode contact hole ECH1 provided in the secondplanarization layer 160. Therefore, the first electrode E1 of the firstlight emitting diode device 300 a may be electrically connected to thesource electrode SE of the first driving transistor Tdr1 through thefirst pixel electrode AE1.

The second pixel electrode AE2 may electrically connect the firstelectrode E1 of the second light emitting diode device 300 b to thesource electrode SE of the second driving transistor Tdr2 and may bedefined as a second anode electrode. The second pixel electrode AE2according to an embodiment may be provided on the second planarizationlayer 160 overlapping the second driving transistor Tdr2 and the firstelectrode E1 of the second light emitting diode device 300 b. The secondpixel electrode AE2 may be electrically connected to the sourceelectrode SE of the second driving transistor Tdr2 through a secondcircuit contact hole CCH2 which is provided to pass through theinterlayer insulation layer 105, the first planarization layer 110, andthe second planarization layer 160, and may be electrically connected tothe first electrode E1 of the second light emitting diode device 300 bthrough a second electrode contact hole ECH2 provided in the secondplanarization layer 160. Therefore, the first electrode E1 of the secondlight emitting diode device 300 b may be electrically connected to thesource electrode SE of the second driving transistor Tdr2 through thesecond pixel electrode AE2.

In this manner, if the light emitting diode display device has a topemission structure, each of the first and second pixel electrodes AE1and AE2 may be formed of a transparent conductive material, and if thelight emitting diode display device has a bottom emission structure, thepixel electrode AE may be formed of a light reflection conductivematerial. In this instance, the transparent conductive material may beindium tin oxide (ITO), indium zinc oxide (IZO), or the like, but is notlimited thereto. The light reflection conductive material may be Al, Ag,Au, Pt, Cu, or the like, but is not limited thereto. Each of the firstand second pixel electrodes AE1 and AE2 including the light reflectionconductive material may be formed of a single layer including the lightreflection conductive material or a multilayer including a plurality ofthe single layers which are stacked.

The common electrode CE may be electrically connected to the secondelectrode E2 of the first light emitting diode device 300 a and thecommon power line CL and may be defined as a cathode electrode. Thecommon electrode CE may be provided on the second planarization layer160 overlapping the second electrode E2 of each of the first and secondlight emitting diode devices 300 a and 300 b and the common power lineCL. In this instance, the common electrode CE may be formed of amaterial which is the same as that of the pixel electrode AE.

One side of the common electrode CE according to an embodiment may beelectrically connected to the common power line CL through a linecontact hole LCH (see FIG. 2) which is provided to pass through the gateinsulation layer 103, the interlayer insulation layer 105, the firstplanarization layer 110, and the second planarization layer 160 whichoverlap the common power line CL. The other side of the common electrodeCE according to an embodiment may be electrically connected to thesecond electrode E2 of the first light emitting diode electrode 300 athrough a third electrode contact hole ECH3 which is provided in thesecond planarization layer 160 to overlap the second electrode E2 of thefirst light emitting diode electrode 300 a, and may be electricallyconnected to the second electrode E2 of the second light emitting diodeelectrode 300 b through a fourth electrode contact hole ECH4 which isprovided in the second planarization layer 160 to overlap the secondelectrode E2 of the second light emitting diode electrode 300 b.Therefore, each of the second electrode E2 of the first light emittingdiode electrode 300 a and the second electrode E2 of the second lightemitting diode electrode 300 b may be electrically connected to thecommon power line CL through the common electrode CE.

The first and second pixel electrodes AE1 and AE2 and the commonelectrode CE may be simultaneously provided through an electrodepatterning process using a lithography process, an etching process, anda deposition process of depositing an electrode material on the secondplanarization layer 160 including the first and second circuit contactholes CCH1 and CCH2, the line contact hole, and the first to fourthelectrode contact holes ECH1 to ECH4. Therefore, in the presentembodiment, since the first and second pixel electrodes AE1 and AE2 andthe common electrode CE connecting the first and second light emittingdiode devices 300 a and 300 b to the pixel circuit PC are simultaneouslyformed, an electrode connection process is simplified, and a processtime taken in a process of connecting the first and second lightemitting diode devices 300 a and 300 b to the pixel circuit PC isconsiderably shortened, thereby enhancing a productivity of the lightemitting diode display device.

The light emitting diode display device according to the presentembodiment may further include a second substrate 500.

The second substrate 500 may be disposed to cover a portion other thanthe pad part of the first substrate 100, thereby protecting a pixelarray provided on the first substrate 100. The second substrate 500 maybe defined as a color filter array substrate, an opposite substrate, oran encapsulation substrate. For example, the second substrate 500according to an embodiment may be formed of a transparent glassmaterial, a transparent plastic material, and/or the like, but is notlimited thereto.

The second substrate 500 according to an embodiment may include a blackmatrix 510.

The black matrix 510 may define an opening area of each subpixel SPprovided on the first substrate 100. That is, the black matrix 510 maybe provided in the light blocking area of the second substrate 500overlapping an area other than the opening area overlapping the emissivearea of each subpixel SP, thereby preventing color mixture betweenadjacent opening areas. The black matrix 510 according to an embodimentmay include a plurality of first light blocking patterns which cover theplurality of gate lines GL, the plurality of common power lines CL, andthe pixel circuit PC of each subpixel SP, a plurality of second lightblocking patterns which cover the plurality of data lines DL and theplurality of driving power lines PL, and a third light blocking patternwhich covers an edge of the second substrate 500. In this instance, thefirst to third light blocking patterns may be provided on the samelayer, and thus, the black matrix 510 may have a mesh form.

In addition, the second substrate 500 may further include a lightextraction layer 530 provided in the opening area defined by the blackmatrix 510. The light extraction layer 530 may be formed of atransparent material and may externally extract light emitted from theemissive area of each subpixel SP. The light extraction layer 530minimizes a step height between the opening area and the black matrix510 provided on the second substrate 500.

In an instance where each of the first and second light emitting diodedevices 300 a and 300 b disposed in each subpixel SP emits white light,the second substrate 500 may include a color filter layer 530 providedin the opening area, instead of the light extraction layer 530.

The color filter layer 530 may include a color filter having a colorcorresponding to a color defined in each subpixel SP. The color filterlayer 530 may transmit only light, having a wavelength of a colorcorresponding to a corresponding subpixel SP, of the white light emittedfrom the corresponding subpixel SP.

The light emitting diode display device according to an embodiment ofthe present disclosure may further include an encapsulation layer 170disposed between the first substrate 100 and the second substrate 500.The encapsulation layer 170 may be an optical clear adhesive (OCA) or anoptical clear resin (OCR), but is not limited thereto.

The light emitting diode display device according to the presentembodiment may further include a reflective layer 101 provided under theemissive area of each subpixel SP.

The reflective layer 101 may be disposed between the floor surface ofeach of the concave portions 130 a and 130 b and the first substrate 100to overlap the emissive area including the first and second lightemitting diode devices 300 a and 300 b. The reflective layer 101according to an embodiment may be formed of a material which is the sameas that of the gate electrode GE of the driving transistors Tdr1 andTdr2, and may be provided on the same layer as the gate electrode GE.The reflective layer 101 may reflect light, which is incident from eachof the first and second light emitting diode devices 300 a and 300 b,toward the second substrate 500. Accordingly, the light emitting diodedisplay device according to the present embodiment may include thereflective layer 101, and thus, may have a top emission structure.

Optionally, the reflective layer 101 may be formed of a material whichis the same as that of the source/drain electrode SE/DE of each of thedriving transistors Tdr1 and Tdr2, and may be provided on the same layeras the source/drain electrode SE/DE.

In the light emitting diode display device according to the presentembodiment, the first and second light emitting diode devices 300 a and300 b of each subpixel SP may be adhered to the floor surface of each ofthe concave portions 130 a and 130 b by an adhesive member 150.

The adhesive member 150 may be disposed between the first and secondlight emitting diode devices 300 a and 300 b and the concave portions130 a and 130 b of each subpixel SP and may attach each of the first andsecond light emitting diode devices 300 a and 300 b onto the floorsurface of a corresponding concave portion of the concave portions 130 aand 130 b, thereby primarily fixing each of the first and second lightemitting diode devices 300 a and 300 b.

The adhesive member 150 according to an embodiment may be attached(coated) on the second portion RP of each of the first and second lightemitting diode devices 300 a and 300 b (i.e., a back surface of thefirst semiconductor layer 310), and thus, in a mounting process ofmounting the light emitting diode device, the adhesive member 150 may beadhered to the floor surface of the first concave portion 130 a and thefloor surface of the second concave portion 130 b.

According to another embodiment, the adhesive member 150 may be dottedonto the floor surface of the first concave portion 130 a and the floorsurface of the second concave portion 130 b and may be spread bypressure which is applied thereto in a mounting process performed forthe light emitting diode device, and thus, may be adhered to the secondportion RP of each of the first and second light emitting diode devices300 a and 300 b. Therefore, the first light emitting diode device 300 amounted on the first concave portion 130 a may be primarilyposition-fixed by the adhesive member 150. Accordingly, according to thepresent embodiment, the mounting process for the light emitting diodedevice may be performed in a method of simply attaching each of thefirst and second light emitting diode devices 300 a and 300 b onto thefloor surface of a corresponding concave portion of the concave portions130 a and 130 b, and thus, a mounting process time taken in performingthe mounting process for the light emitting diode device is shortened.

In other embodiments, the adhesive member 150 may be coated on the top110 a of the first planarization layer 110, the floor surface and aninclined surface of the first concave portion 130 a, and the floorsurface and an inclined surface of the second concave portion 130 b.That is, the adhesive member 150 may be provided to wholly cover aportion of a front surface of the first planarization layer 110 exceptthe contact holes. In other words, the adhesive member 150 may bedisposed between the first planarization layer 110 and the secondplanarization layer 160 and may be disposed between the firstplanarization layer 110 and each of the first light emitting diodedevices 300 a and 300 b. In other embodiments, the adhesive member 150may be coated on the whole top 110 a of the first planarization layer110, where the concave portions 130 a and 130 b are provided, to acertain thickness. A portion of the adhesive member 150 coated on thetop 110 a of the first planarization layer 110, where the contact holesare to be provided, may be removed when forming the contact holes.Therefore, in the present embodiment, immediately before a mountingprocess for the light emitting diode device, the adhesive member 150 maybe coated on the whole top 110 a of the first planarization layer 110 tohave a certain thickness, and thus, according to the present embodiment,a process time taken in forming the adhesive member 150 is shortened.

In the present embodiment, the adhesive member 150 may be provided onthe whole top of the first planarization layer 110, and thus, the secondplanarization layer 160 according to the present embodiment is providedto cover the adhesive member 150.

A mounting process for a light emitting diode device according to anembodiment may include a process of mounting red first and second lightemitting diode devices on each of red subpixels SP1, a process ofmounting green first and second light emitting diode devices on each ofgreen subpixels SP2, and a process of mounting blue first and secondlight emitting diode devices on each of blue subpixels SP3, andmoreover, may further include a process of mounting white first andsecond light emitting diode devices on each of white subpixels.

The mounting process for the light emitting diode device according to anembodiment may include only a process of mounting the white first andsecond light emitting diode devices on each of subpixels. In thisinstance, the first substrate 100 or the second substrate 500 mayinclude a color filter layer overlapping each subpixel. The color filterlayer may transmit only light, having a wavelength of a colorcorresponding to a corresponding subpixel, of white light.

The mounting process for the light emitting diode device according to anembodiment may include only a process of mounting first and second lightemitting diode devices having a first color on each subpixel. In thisinstance, the first substrate 100 or the second substrate 500 mayinclude a wavelength conversion layer and the color filter layeroverlapping each subpixel. The wavelength conversion layer may emitlight of a second color, based on some of light of the first colorincident from the first and second light emitting diode devices havingthe first color. The color filter layer may transmit only light, havinga wavelength of a color corresponding to a corresponding subpixel, ofwhite light based on a combination of the light of the first color andthe light of the second color. In this instance, the first color may beblue, and the second color may be yellow.

FIG. 6 is a diagram for describing a modification embodiment of theconcave portion illustrated in FIG. 2.

Referring to FIG. 6, first and second concave portions 130 a and 130 bprovided in each of a plurality of subpixels SP according to themodification embodiment may have the same depth and may be providedconcavely from a first planarization layer 110 to have different depthsD1 to D3 in each subpixel SP. In this instance, the depths D1 to D3 ofeach of the first and second concave portions 130 a and 130 b may bedefined as a distance between a top 110 a of the first planarizationlayer 110 and a floor surface 110 b of each of the first and secondconcave portions 130 a and 130 b.

The first concave portion 130 a provided in each subpixel SP may beprovided to have the different depths D1 to D3 in each of at least threeadjacent subpixels SP1 to SP3 configuring one unit pixel UP. That is,the first concave portions 130 a may be provided to have the differentdepths D1 to D3 from the first planarization layer 110, based on aheight of a light emitting diode device which is to be provided in acorresponding subpixel, thereby removing or minimizing a heightdeviation (or a step height) between light emitting diode devices bycolors. The second concave portion 130 b provided in each subpixel SPmay be formed to have the same shape and depth as those of the firstconcave portion 130 a.

In order to realize a color image, the light emitting diode displaydevice according to the present embodiment may include a red subpixelSP1, a green subpixel SP2, and a blue subpixel SP3, and the lightemitting diode device may be provided by colors and may be disposed inthe first and second concave portions 130 a and 130 b provided in asubpixel having a corresponding color. In this instance, the color-basedlight emitting diode devices may have different heights (or thicknesses)due to a process error of a manufacturing process. For example,thicknesses of the color-based light emitting diode devices may bethickened in the order of red, green, and blue. In this instance, thedepths D1 to D3 of the first and second concave portions 130 a and 130 bmay be deeply provided in the order of the red subpixel SP1, the greensubpixel SP2, and the blue subpixel SP3, based on a height of acorresponding light emitting diode device.

Therefore, in the present embodiment, the depths of the first and secondconcave portions 130 a and 130 b provided in each subpixel may bedifferently set based on a height (or a thickness) of the light emittingdiode device which is to be provided in a corresponding subpixel, andthus, uppermost surfaces (for example, tops of first electrodes E1) oflight emitting diode devices 300 a and 300 b disposed in each subpixelmay be disposed on the same horizontal line HL, thereby preventing anopen defect, where first electrodes (or second electrodes) of the lightemitting diode devices are not exposed, from occurring due to athickness deviation between color-based light emitting diode devices ina patterning process for first and second electrode contact holes. Also,in the present embodiment, in the top emission structure, an opticaldistance between a reflective layer 101 and the light emitting diodedevice of each subpixel is optimized by using the first and secondconcave portions 130 a and 130 b which are provided to the differentdepths D1 to D3 in each subpixel, and thus, a reflection efficiency ofthe reflective layer 101 is improved, thereby maximizing a lightefficiency of each of the light emitting diode devices.

FIG. 7 is a diagram for describing the subpixel according to anembodiment of the present disclosure illustrated in FIG. 2 andillustrates an example where a configuration of a pixel circuit ismodified. Hereinafter, therefore, a pixel circuit and elements relevantthereto will be described, and descriptions of the other elements arenot repeated.

Referring to FIG. 7 along with FIG. 1, the pixel circuit PC of eachsubpixel according to the present embodiment may include a switchingtransistor Tsw, a storage capacitor Cst, a first current output partCOP1, a second current output part COP2, and a voltage initializationpart VIP.

The switching transistor Tsw may include a gate electrode connected to afirst gate line GL1, a drain electrode connected to a data line DL, anda source electrode connected to a first node NE In this instance, thesource electrode and the drain electrode of the switching transistor Tswmay switch therebetween depending on a direction of a current. During asampling period, the switching transistor Tsw may be turned on accordingto a first gate signal supplied through the first gate line GL1 and maysupply a data signal, supplied through the data line DL, to the firstnode N1.

The storage capacitor Cst may include a first terminal connected to thefirst node N1 and a second terminal connected to the second node (or acommon node) N2. That is, the storage capacitor Cst may be provided tohave a certain capacitance in an overlapping area between the first nodeN1, connected to the source electrode of the switching transistor Tsw,and the second node N2 connected to the gate electrode of a firstdriving transistor Tdr1. The storage capacitor Cst may store adifference voltage between the first node N1 and the second node N2 andmay supply the stored voltage to the first current output part COP1 andthe second current output part COP2 in common. In more detail, thestorage capacitor Cst may store a voltage corresponding to the datasignal from the switching transistor Tsw and may supply the storedvoltage to the first current output part COP1 and the second currentoutput part COP2 in common.

The first current output part COP1 may be turned on by the voltagecorresponding to the data signal supplied from the storage capacitor Cstto the second node N2 and may supply a data current to a first lightemitting diode device 300 a. The first current output part COP1 mayinclude the first driving transistor Tdr1.

The first driving transistor Tdr1 may include a gate electrode connectedto the second node N2, a drain electrode connected to a driving powerline PL, and a source electrode connected to an anode terminal of thefirst light emitting diode device 300 a. The first driving transistorTdr1 may be turned on by a voltage of the second node N2 to control theamount of current flowing from the driving power line PL to the firstlight emitting diode device 300 a.

The first current output part COP1 according to an embodiment mayfurther include a first emission control transistor Tem1 connectedbetween the first driving transistor Tdr1 and the first light emittingdiode device 300 a.

The first emission control transistor Tem1 may include a gate electrodeconnected to an emission control line ECL, a drain electrode connectedto the source electrode of the first driving transistor Tdr1, and asource electrode connected to an anode terminal of the first lightemitting diode device 300 a. During a pre-initialization period forpre-initializing the source electrode of the first driving transistorTdr1, the first emission control transistor Tem1 may be turned on by anemission control signal supplied through the emission control line ECLand may provide a path for pre-initializing the source electrode of thefirst driving transistor Tdr1 to a reference voltage Vref. Also, duringan emission period, the first emission control transistor Tem1 may beturned on by the emission control signal supplied through the emissioncontrol line ECL and may supply a data current, output from the firstdriving transistor Tdr1, to the first light emitting diode device 300 a.

The source electrode of the first emission control transistor Tem1, asillustrated in FIG. 4, may be connected to, through a first pixelelectrode AE1, a first electrode E1 of the first light emitting diodedevice 300 a disposed in a first concave portion 130 a.

The second current output part COP2 may be turned on by the voltagecorresponding to the data signal supplied from the storage capacitor Cstto the second node N2 and may supply a data current to a second lightemitting diode device 300 b. The second current output part COP2according to an embodiment may include a second driving transistor Tdr2.

The second driving transistor Tdr2 may include a gate electrodeconnected to the second node N2, a drain electrode connected to thedriving power line PL, and a source electrode connected to a firstelectrode of the second light emitting diode device 300 b. The seconddriving transistor Tdr2 may be turned on by a voltage of the second nodeN2 to control the amount of current flowing from the driving power linePL to the second light emitting diode device 300 b.

The second driving transistor Tdr2 may be formed along with the firstdriving transistor Tdr1 and may have the same size as that of the firstdriving transistor Tdr1.

The second current output part COP2 according to an embodiment mayfurther include a second emission control transistor Tem2 connectedbetween the second driving transistor Tdr2 and the second light emittingdiode device 300 b.

The second emission control transistor Tem2 may include a gate electrodeconnected to the emission control line ECL, a drain electrode connectedto the source electrode of the second driving transistor Tdr2, and asource electrode connected to an anode terminal of the second lightemitting diode device 300 b. Also, during the emission period, thesecond emission control transistor Tem2 may be turned on by the emissioncontrol signal supplied through the emission control line ECL and maysupply a data current, output from the second driving transistor Tdr2,to the second light emitting diode device 300 b.

The source electrode of the second emission control transistor Tem2, asillustrated in FIG. 4, may be connected to, through a second pixelelectrode AE2, a first electrode E1 of the second light emitting diodedevice 300 b disposed in a second concave portion 130 b.

In the pixel circuit PC, one of the first and second current outputparts COP1 and COP2 may be a redundancy pixel circuit which ispreviously provided in each of subpixels SP1 to SP3 for solving anoperation defect of each of the first and second light emitting diodedevices 300 a and 300 b provided in each of the subpixels SP1 to SP3.

The voltage initialization part VIP may pre-initialize the sourceelectrode of the first driving transistor Tdr1 to the reference voltageVref during the pre-initialization period, and during an initializationperiod, the voltage initialization part VIP may initialize the voltagestored in the storage capacitor Cst to the reference voltage Vref. Thevoltage initialization part VIP according to an embodiment may include afirst transistor T1, a second transistor T2, and a third transistor T3.

The first transistor T1 may include a gate electrode connected to asecond gate line GL2, a drain electrode connected to the second node N2,and a source electrode connected to the source electrode of the firstdriving transistor Tdr1. During the initialization period and thesampling period, the first transistor T1 may be turned on by a secondgate signal supplied through the second gate line GL2 and may connectthe gate electrode of the first driving transistor Tdr1 to the sourceelectrode.

The second transistor T2 may include a gate electrode connected to theemission control line ECL, a drain electrode connected to a referencepower line RL, and a source electrode connected to the first node N1.During the pre-initialization period and the initialization period, thesecond transistor T2 may be turned on by the emission control signalsupplied through the emission control line ECL and may supply thereference voltage, supplied through the reference power line RL, to thefirst node N1.

The third transistor T3 may include a gate electrode connected to thesecond gate line GL2, a drain electrode connected to the reference powerline RL, and a source electrode connected to a third node N3 connectedto the source electrode of the first emission control transistor Tem1.During the initialization period and the sampling period, the thirdtransistor T3 may be turned on by the second gate signal suppliedthrough the second gate line GL2 and may supply the reference voltage,supplied through the reference power line RL, to the third node N3.

In an embodiment of the present disclosure described above, the pixelcircuit PC of each subpixel is not limited to FIGS. 3 to 7. In otherembodiments, the pixel circuit PC may further include at least oneauxiliary transistor and at least one auxiliary capacitor forcompensating for a threshold voltage of a driving transistor, inaddition to a switching transistor and a current output part.

In addition, in an embodiment of the present disclosure described above,each subpixel has been described above as including two light emittingdiode devices, but is not limited thereto. In other embodiments, eachsubpixel may include first to Nth (where N is a natural number equal toor more than two) light emitting diode devices and a pixel circuitincluding first to Nth driving transistors which respectively supply adata current to each of the first to Nth light emitting diode devices.In this instance, each subpixel may include one or N concave portionswhere each of the first to Nth light emitting diode devices isaccommodated into one accommodation space or is individuallyaccommodated.

As described above, in the light emitting diode display device accordingto the embodiments of the present disclosure, a screen defect caused bya defect of a micro light emitting device is prevented or reduced.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present disclosurewithout departing from the spirit or scope of the disclosures. Thus, itis intended that the present disclosure covers the modifications andvariations of this disclosure provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A light emitting diode display device comprising:a plurality of pixels displaying an image based on a data signal, theplurality of pixels each including: a first and second light emittingdiode devices emitting light; a first and second driving transistorselectrically connected to the first and second light emitting diodedevices respectively; an insulation layer covering the first and seconddriving transistors; and a planarization layer on the insulation layer;and an adhesive member between the insulation layer and the first andthe second light emitting diode devices, wherein each of the first andsecond light emitting diode devices includes: a first portion includinga first electrode and a second electrode; and a second portion oppositeto the first portion, and wherein the adhesive member is interposedbetween the second portion of each of the first and the second lightemitting diode devices and the insulation layer.
 2. The light emittingdiode display device of claim 1, wherein when any one of the first andthe second light emitting diode devices have a defect, remaining lightemitting diode devices of the first and the second light emitting diodedevices are used as a redundancy light emitting diode device.
 3. Thelight emitting diode display device of claim 1, wherein each of thefirst and the second light emitting diode devices comprises: a firstsemiconductor layer; an active layer provided on one side of the firstsemiconductor layer; and a second semiconductor layer provided on theactive layer, wherein the first electrode is provided on the secondsemiconductor layer, and wherein the second electrode is provided onanother side of the first semiconductor layer, and is physicallyseparate from the active layer and the second semiconductor layer. 4.The light emitting diode display device of claim 3, wherein each of theplurality of pixels further comprises: a common electrode connected tothe second electrodes of the first and the second light emitting diodedevices; and first and second pixel electrodes respectively configuredto connect the first electrodes of the first and the second lightemitting diode devices to the first and the second driving transistorsin a one-to-one relationship.
 5. The light emitting diode display deviceof claim 3, wherein the planarization layer includes a plurality ofconcave portions, and each of the first and the second light emittingdiode devices is disposed in the plurality of concave portionsrespectively.
 6. The light emitting diode display device of claim 1,wherein the planarization layer comprises: a first planarization layerdisposed on the insulation layer; and a second planarization layerdisposed on the first planarization layer and the first and the secondlight emitting diode devices, and wherein the first and the second lightemitting diode devices are embedded in the second planarization layer.7. The light emitting diode display device of claim 1, wherein the firstelectrodes of the first and the second light emitting diode devices aredisposed facing laterally each other.
 8. The light emitting diodedisplay device of claim 7, wherein the first electrodes of the first andthe second light emitting diode devices are electrically connected toeach other.
 9. The light emitting diode display device of claim 1,wherein a distance between the second electrodes of the first and thesecond light emitting diode devices is larger than a distance betweenthe first electrodes of the first and the second light emitting diodedevices.
 10. A light emitting diode display device comprising: aplurality of pixels displaying an image based on a data signal, theplurality of pixels each including: a first and second light emittingdiode devices emitting light; a first and second driving transistorselectrically connected to the first and second light emitting diodedevices respectively; an insulation layer covering the first and seconddriving transistors; and a planarization layer on the insulation layer,wherein each of the first and second light emitting diode devicesincludes: a first portion including a first electrode and a secondelectrode; and a second portion opposite to the first portion, andwherein the first electrodes of the first and the second light emittingdiode devices are disposed facing laterally each other.
 11. The lightemitting diode display device of claim 9, wherein a distance between thesecond electrodes of the first and the second light emitting diodedevices is bigger than a distance between the first electrodes of thefirst and the second light emitting diode devices.
 12. The lightemitting diode display device of claim 10, wherein when any one of thefirst and the second light emitting diode devices have a defect,remaining light emitting diode devices of the first and the second lightemitting diode devices are used as a redundancy light emitting diodedevice.
 13. The light emitting diode display device of claim 10, whereineach of the first and the second light emitting diode devices comprises:a first semiconductor layer; an active layer provided on one side of thefirst semiconductor layer; and a second semiconductor layer provided onthe active layer, wherein the first electrode is provided on the secondsemiconductor layer, and wherein the second electrode is provided onanother side of the first semiconductor layer, and is physicallyseparate from the active layer and the second semiconductor layer. 14.The light emitting diode display device of claim 13, wherein each of theplurality of pixels further comprises: a common electrode connected tothe second electrodes of the first and the second light emitting diodedevices; and first and second pixel electrodes respectively configuredto connect the first electrodes of the first and the second lightemitting diode devices to the first and the second driving transistorsin a one-to-one relationship.
 15. The light emitting diode displaydevice of claim 13, wherein the planarization layer includes a pluralityof concave portions, and each of the first and the second light emittingdiode devices is disposed in the plurality of concave portionsrespectively.
 16. The light emitting diode display device of claim 11,wherein the planarization layer comprises: a first planarization layerdisposed on the insulation layer; and a second planarization layerdisposed on the first planarization layer and the first and the secondlight emitting diode devices, and wherein the first and the second lightemitting diode devices are embedded in the second planarization layer.17. The light emitting diode display device of claim 11, wherein thefirst electrodes of the first and the second light emitting diodedevices are disposed facing laterally each other.
 18. The light emittingdiode display device of claim 17, wherein the first electrodes of thefirst and the second light emitting diode devices are electricallyconnected to each other.
 19. The light emitting diode display device ofclaim 11, wherein a distance between the second electrodes of the firstand the second light emitting diode devices is larger than a distancebetween the first electrodes of the first and the second light emittingdiode devices.
 20. The light emitting diode display device of claim 11,further comprising an adhesive member between the insulation layer andthe first and the second light emitting diode devices.